Genesis
This commit is contained in:
seb
172
README.md
Normal file
172
README.md
Normal file
@@ -0,0 +1,172 @@
|
||||
# ⚙ react-automat
|
||||
|
||||
> Zero-dependency higher-order state container for React `PureComponent`. State lives in module scope (independent of mounting). Components read state synchronously in `constructor` and subscribe in `componentDidMount`. No Context, hooks, or HOCs.
|
||||
|
||||
[](https://sebgreen.net/automat/)
|
||||
[](LICENSE)
|
||||
|
||||
```bash
|
||||
npm install react-automat
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## 1. Complete Type Signatures
|
||||
|
||||
```ts
|
||||
import type { PureComponent } from 'react';
|
||||
|
||||
export interface AutomatOptions<T> {
|
||||
name?: string | null; // window.__AUTOMATS__ key & Automat.get(name)
|
||||
persist?: boolean; // false = window (default), true = IndexedDB
|
||||
url?: string | null; // Auto-triggers fetcher(url) on init
|
||||
fetcher?: (url: string, automat?: Automat<T, any>) => Promise<T>;
|
||||
}
|
||||
|
||||
export type Selector<T, S = any> = keyof T | (keyof T)[] | ((state: T) => S | null | undefined);
|
||||
|
||||
export interface ScopedSlice<S> {
|
||||
readonly state: S;
|
||||
subscribe(target: PureComponent | ((slice: S) => void)): () => void;
|
||||
}
|
||||
|
||||
export interface BlobResource {
|
||||
blob: Blob; url: string; size: number; type: string; loadedAt: string;
|
||||
revoke: () => void; // Auto-called on setDirty() / dispose() to release memory
|
||||
}
|
||||
|
||||
export interface SSEOptions<T = any, A = any> {
|
||||
onMessage?: (data: any, event: string, automat: Automat<T, A>) => void;
|
||||
events?: Record<string, (data: any, automat: Automat<T, A>) => void>;
|
||||
onError?: (err: any, automat: Automat<T, A>) => void;
|
||||
}
|
||||
|
||||
export class Automat<T = any, A = Record<string, Function>> {
|
||||
constructor(initialState?: T | null, actions?: A, options?: AutomatOptions<T>);
|
||||
|
||||
readonly state: T;
|
||||
getState(): T;
|
||||
setState(partial: Partial<T> | ((prev: T) => Partial<T>)): T;
|
||||
readonly actions: A;
|
||||
|
||||
readonly isReady: boolean;
|
||||
readonly isDirty: boolean;
|
||||
readonly ready: Promise<T>; // Re-awaitable after setDirty()
|
||||
readonly name: string | null;
|
||||
readonly persist: boolean;
|
||||
readonly url: string | null;
|
||||
readonly subscriberCount: number;
|
||||
|
||||
subscribe(target: PureComponent | ((state: T, partial?: Partial<T>) => void), selector?: Selector<T>): () => void;
|
||||
select<S = any>(selector: Selector<T, S>): ScopedSlice<S>;
|
||||
unsubscribe(target: any): void;
|
||||
|
||||
subscribeTo<U = any>(
|
||||
upstream: Automat<U, any>,
|
||||
transform: (upstreamState: U, currentState: T) => Partial<T> | null | undefined,
|
||||
options?: { cascadeDirty?: boolean | ((upstream: U, current: T) => boolean) }
|
||||
): this;
|
||||
|
||||
invalidateWith<U = any>(upstream: Automat<U, any>, filterFn?: (upstream: U, current: T) => boolean): this;
|
||||
onDirty(fn: (automat: this) => void): () => void;
|
||||
|
||||
setDirty(): Promise<T>; // Resets state to null/default, revokes blobs, cascades, defers if unmounted
|
||||
reload(): Promise<T>; // Silent background re-fetch; preserves state & isReady=true
|
||||
refresh(): Promise<T>; // Alias for reload()
|
||||
read(): T; // For Suspense: throws ready promise if unready; triggers deferred load if dirty
|
||||
|
||||
clearPersistence(): Promise<void>;
|
||||
dispose(): void; // Unsubs all, revokes blobs, deletes from window registry
|
||||
|
||||
static get<T = any, A = any>(name: string): Automat<T, A> | undefined;
|
||||
}
|
||||
|
||||
// Fetchers & SSE
|
||||
export function fetchJson<T = any>(url: string, options?: RequestInit): Promise<T>;
|
||||
export function fetchBlob(url: string, options?: RequestInit): Promise<BlobResource>;
|
||||
export const fetchImageBlob: typeof fetchBlob;
|
||||
export const fetchPdfBlob: typeof fetchBlob;
|
||||
export function connectSSE<T, A>(automat: Automat<T, A>, url: string, options?: SSEOptions<T, A>): { eventSource: EventSource | null; close: () => void };
|
||||
export function createSSEFetcher(sseUrl: string, baseFetcher?: Function, sseOptions?: SSEOptions): (url: string, automat?: any) => Promise<any>;
|
||||
```
|
||||
|
||||
## 2. Canonical Usage Patterns
|
||||
|
||||
### A. PureComponent Subscription
|
||||
```jsx
|
||||
import { PureComponent } from 'react';
|
||||
import { Automat } from 'react-automat';
|
||||
|
||||
const store = new Automat({ count: 0 }, { inc: () => store.setState({ count: store.state.count + 1 }) });
|
||||
|
||||
class Counter extends PureComponent {
|
||||
constructor(props) { super(props); this.state = store.state; } // Sync read, never stale
|
||||
componentDidMount() { this.unsub = store.subscribe(this); } // Auto-calls this.setState(partial)
|
||||
componentWillUnmount() { this.unsub(); }
|
||||
render() { return <button onClick={store.actions.inc}>{this.state.count}</button>; }
|
||||
}
|
||||
```
|
||||
|
||||
### B. Fine-Grained Selectors (Shallow-guarded, 0 renders if slice unchanged)
|
||||
```js
|
||||
store.subscribe(this, 'count'); // Single key
|
||||
store.subscribe(this, ['theme', 'locale']); // Multi key
|
||||
store.subscribe(this, (s) => ({ items: s.list.length }));// Projection function
|
||||
```
|
||||
|
||||
### C. Unconnected Component via Window (Zero imports of store file)
|
||||
```js
|
||||
const store = Automat.get('cart'); // or window.__AUTOMATS__?.get('cart')
|
||||
this.state = { count: store?.state?.items?.length || 0 };
|
||||
this.unsub = store?.subscribe(this, (s) => ({ count: s.items.length }));
|
||||
```
|
||||
|
||||
### D. Backend API: React Suspense vs Standard
|
||||
```jsx
|
||||
const user = new Automat(null, {}, { url: '/api/user' });
|
||||
|
||||
// Suspense: throws promise while unready
|
||||
const Profile = () => <div>{user.read().name}</div>;
|
||||
|
||||
// Standard: check isReady
|
||||
class ProfileStandard extends PureComponent {
|
||||
constructor(props) { super(props); this.state = { u: user.state }; }
|
||||
componentDidMount() { this.unsub = user.subscribe(this, (u) => ({ u })); }
|
||||
componentWillUnmount() { this.unsub(); }
|
||||
render() { return !user.isReady ? <Spinner /> : <div>{this.state.u.name}</div>; }
|
||||
}
|
||||
```
|
||||
|
||||
### E. Cascading Invalidation, Blobs & Memory Freeing
|
||||
```js
|
||||
const all = new Automat(null, {}, { name: 'photos/all', url: '/api/photos' });
|
||||
const p1 = new Automat(null, {}, { name: 'photo/1', url: '/api/photos/1', fetcher: fetchImageBlob });
|
||||
p1.invalidateWith(all); // p1 cascades setDirty() when all.setDirty() is called
|
||||
|
||||
all.setDirty(); // p1 auto-revokes held Blob URL, resets state=null, defers reload if unmounted
|
||||
```
|
||||
|
||||
### F. SSE Remote Trigger
|
||||
```js
|
||||
const live = new Automat({}, {
|
||||
onSSETrigger(data, event, store) {
|
||||
if (event === 'invalidate') store.setDirty();
|
||||
if (event === 'reload') store.reload();
|
||||
}
|
||||
});
|
||||
connectSSE(live, '/api/stream');
|
||||
```
|
||||
|
||||
## 3. Decision Matrix: `setDirty()` vs `reload()`
|
||||
|
||||
| Method | `isReady` | State during fetch | Suspense | Unmounted | Use Case |
|
||||
|---|---|---|---|---|---|
|
||||
| `setDirty()` | `false` | Resets to `null`/init | Throws fallback | Deferred until mount/read | Cache bust, logout, hard reset |
|
||||
| `reload()` | `true` | Preserved | Never suspends | Immediate fetch | Polling, pull-to-refresh, sync |
|
||||
|
||||
## 4. Invariant Rules
|
||||
- Read `store.state` synchronously in `constructor(props)` — never in render bodies.
|
||||
- Subscribe in `componentDidMount()` & store the returned `unsub`; unsubscribe in `componentWillUnmount()`.
|
||||
- Never mutate `store.state` directly (`store.state.x = 1` ❌); use `store.setState({ x })` or actions.
|
||||
- Pass selectors to `subscribe(this, selector)` on multi-key stores to skip redundant renders.
|
||||
- Never wrap components in Context Providers, HOCs, or custom hooks.
|
||||
Reference in New Issue
Block a user